trunk/src/main/org/apache/tools/tar/TarEntry.java - ant - Git at Google

 /*
  *  Licensed to the Apache Software Foundation (ASF) under one or more
  *  contributor license agreements.  See the NOTICE file distributed with
  *  this work for additional information regarding copyright ownership.
  *  The ASF licenses this file to You under the Apache License, Version 2.0
  *  (the "License"); you may not use this file except in compliance with
  *  the License.  You may obtain a copy of the License at
  *
  *      http://www.apache.org/licenses/LICENSE-2.0
  *
  *  Unless required by applicable law or agreed to in writing, software
  *  distributed under the License is distributed on an "AS IS" BASIS,
  *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  *  See the License for the specific language governing permissions and
  *  limitations under the License.
  *
  */

 /*
  * This package is based on the work done by Timothy Gerard Endres
  * (time@ice.com) to whom the Ant project is very grateful for his great code.
  */

 package org.apache.tools.tar;

 import java.io.File;
 import java.util.Date;
 import java.util.Locale;

 /**
  * This class represents an entry in a Tar archive. It consists
  * of the entry's header, as well as the entry's File. Entries
  * can be instantiated in one of three ways, depending on how
  * they are to be used.
  * <p>
  * TarEntries that are created from the header bytes read from
  * an archive are instantiated with the TarEntry( byte[] )
  * constructor. These entries will be used when extracting from
  * or listing the contents of an archive. These entries have their
  * header filled in using the header bytes. They also set the File
  * to null, since they reference an archive entry not a file.
  * <p>
  * TarEntries that are created from Files that are to be written
  * into an archive are instantiated with the TarEntry( File )
  * constructor. These entries have their header filled in using
  * the File's information. They also keep a reference to the File
  * for convenience when writing entries.
  * <p>
  * Finally, TarEntries can be constructed from nothing but a name.
  * This allows the programmer to construct the entry by hand, for
  * instance when only an InputStream is available for writing to
  * the archive, and the header information is constructed from
  * other information. In this case the header fields are set to
  * defaults and the File is set to null.
  *
  * <p>
  * The C structure for a Tar Entry's header is:
  * <pre>
  * struct header {
  * char name[NAMSIZ];
  * char mode[8];
  * char uid[8];
  * char gid[8];
  * char size[12];
  * char mtime[12];
  * char chksum[8];
  * char linkflag;
  * char linkname[NAMSIZ];
  * char magic[8];
  * char uname[TUNMLEN];
  * char gname[TGNMLEN];
  * char devmajor[8];
  * char devminor[8];
  * } header;
  * </pre>
  *
  */

 public class TarEntry implements TarConstants {
     /** The entry's name. */
     private StringBuffer name;

     /** The entry's permission mode. */
     private int mode;

     /** The entry's user id. */
     private int userId;

     /** The entry's group id. */
     private int groupId;

     /** The entry's size. */
     private long size;

     /** The entry's modification time. */
     private long modTime;

     /** The entry's link flag. */
     private byte linkFlag;

     /** The entry's link name. */
     private StringBuffer linkName;

     /** The entry's magic tag. */
     private StringBuffer magic;

     /** The entry's user name. */
     private StringBuffer userName;

     /** The entry's group name. */
     private StringBuffer groupName;

     /** The entry's major device number. */
     private int devMajor;

     /** The entry's minor device number. */
     private int devMinor;

     /** The entry's file reference */
     private File file;

     /** Maximum length of a user's name in the tar file */
     public static final int MAX_NAMELEN = 31;

     /** Default permissions bits for directories */
     public static final int DEFAULT_DIR_MODE = 040755;

     /** Default permissions bits for files */
     public static final int DEFAULT_FILE_MODE = 0100644;

     /** Convert millis to seconds */
     public static final int MILLIS_PER_SECOND = 1000;

     /**
      * Construct an empty entry and prepares the header values.
      */
     private TarEntry () {
         this.magic = new StringBuffer(TMAGIC);
         this.name = new StringBuffer();
         this.linkName = new StringBuffer();

         String user = System.getProperty("user.name", "");

         if (user.length() > MAX_NAMELEN) {
             user = user.substring(0, MAX_NAMELEN);
         }

         this.userId = 0;
         this.groupId = 0;
         this.userName = new StringBuffer(user);
         this.groupName = new StringBuffer("");
         this.file = null;
     }

     /**
      * Construct an entry with only a name. This allows the programmer
      * to construct the entry's header "by hand". File is set to null.
      *
      * @param name the entry name
      */
     public TarEntry(String name) {
         this();

         boolean isDir = name.endsWith("/");

         this.devMajor = 0;
         this.devMinor = 0;
         this.name = new StringBuffer(name);
         this.mode = isDir ? DEFAULT_DIR_MODE : DEFAULT_FILE_MODE;
         this.linkFlag = isDir ? LF_DIR : LF_NORMAL;
         this.userId = 0;
         this.groupId = 0;
         this.size = 0;
         this.modTime = (new Date()).getTime() / MILLIS_PER_SECOND;
         this.linkName = new StringBuffer("");
         this.userName = new StringBuffer("");
         this.groupName = new StringBuffer("");
         this.devMajor = 0;
         this.devMinor = 0;

     }

     /**
      * Construct an entry with a name and a link flag.
      *
      * @param name the entry name
      * @param linkFlag the entry link flag.
      */
     public TarEntry(String name, byte linkFlag) {
         this(name);
         this.linkFlag = linkFlag;
     }

     /**
      * Construct an entry for a file. File is set to file, and the
      * header is constructed from information from the file.
      *
      * @param file The file that the entry represents.
      */
     public TarEntry(File file) {
         this();

         this.file = file;

         String fileName = file.getPath();
         String osname = System.getProperty("os.name").toLowerCase(Locale.US);

         if (osname != null) {

             // Strip off drive letters!
             // REVIEW Would a better check be "(File.separator == '\')"?

             if (osname.startsWith("windows")) {
                 if (fileName.length() > 2) {
                     char ch1 = fileName.charAt(0);
                     char ch2 = fileName.charAt(1);

                     if (ch2 == ':'
                             && ((ch1 >= 'a' && ch1 <= 'z')
                                 || (ch1 >= 'A' && ch1 <= 'Z'))) {
                         fileName = fileName.substring(2);
                     }
                 }
             } else if (osname.indexOf("netware") > -1) {
                 int colon = fileName.indexOf(':');
                 if (colon != -1) {
                     fileName = fileName.substring(colon + 1);
                 }
             }
         }

         fileName = fileName.replace(File.separatorChar, '/');

         // No absolute pathnames
         // Windows (and Posix?) paths can start with "\\NetworkDrive\",
         // so we loop on starting /'s.
         while (fileName.startsWith("/")) {
             fileName = fileName.substring(1);
         }

         this.linkName = new StringBuffer("");
         this.name = new StringBuffer(fileName);

         if (file.isDirectory()) {
             this.mode = DEFAULT_DIR_MODE;
             this.linkFlag = LF_DIR;

             if (this.name.charAt(this.name.length() - 1) != '/') {
                 this.name.append("/");
             }
         } else {
             this.mode = DEFAULT_FILE_MODE;
             this.linkFlag = LF_NORMAL;
         }

         this.size = file.length();
         this.modTime = file.lastModified() / MILLIS_PER_SECOND;
         this.devMajor = 0;
         this.devMinor = 0;
     }

     /**
      * Construct an entry from an archive's header bytes. File is set
      * to null.
      *
      * @param headerBuf The header bytes from a tar archive entry.
      */
     public TarEntry(byte[] headerBuf) {
         this();
         parseTarHeader(headerBuf);
     }

     /**
      * Determine if the two entries are equal. Equality is determined
      * by the header names being equal.
      *
      * @param it Entry to be checked for equality.
      * @return True if the entries are equal.
      */
     public boolean equals(TarEntry it) {
         return getName().equals(it.getName());
     }

     /**
      * Determine if the two entries are equal. Equality is determined
      * by the header names being equal.
      *
      * @param it Entry to be checked for equality.
      * @return True if the entries are equal.
      */
     public boolean equals(Object it) {
         if (it == null || getClass() != it.getClass()) {
             return false;
         }
         return equals((TarEntry) it);
     }

     /**
      * Hashcodes are based on entry names.
      *
      * @return the entry hashcode
      */
     public int hashCode() {
         return getName().hashCode();
     }

     /**
      * Determine if the given entry is a descendant of this entry.
      * Descendancy is determined by the name of the descendant
      * starting with this entry's name.
      *
      * @param desc Entry to be checked as a descendent of this.
      * @return True if entry is a descendant of this.
      */
     public boolean isDescendent(TarEntry desc) {
         return desc.getName().startsWith(getName());
     }

     /**
      * Get this entry's name.
      *
      * @return This entry's name.
      */
     public String getName() {
         return name.toString();
     }

     /**
      * Set this entry's name.
      *
      * @param name This entry's new name.
      */
     public void setName(String name) {
         this.name = new StringBuffer(name);
     }

     /**
      * Set the mode for this entry
      *
      * @param mode the mode for this entry
      */
     public void setMode(int mode) {
         this.mode = mode;
     }

     /**
      * Get this entry's link name.
      *
      * @return This entry's link name.
      */
     public String getLinkName() {
         return linkName.toString();
     }

     /**
      * Get this entry's user id.
      *
      * @return This entry's user id.
      */
     public int getUserId() {
         return userId;
     }

     /**
      * Set this entry's user id.
      *
      * @param userId This entry's new user id.
      */
     public void setUserId(int userId) {
         this.userId = userId;
     }

     /**
      * Get this entry's group id.
      *
      * @return This entry's group id.
      */
     public int getGroupId() {
         return groupId;
     }

     /**
      * Set this entry's group id.
      *
      * @param groupId This entry's new group id.
      */
     public void setGroupId(int groupId) {
         this.groupId = groupId;
     }

     /**
      * Get this entry's user name.
      *
      * @return This entry's user name.
      */
     public String getUserName() {
         return userName.toString();
     }

     /**
      * Set this entry's user name.
      *
      * @param userName This entry's new user name.
      */
     public void setUserName(String userName) {
         this.userName = new StringBuffer(userName);
     }

     /**
      * Get this entry's group name.
      *
      * @return This entry's group name.
      */
     public String getGroupName() {
         return groupName.toString();
     }

     /**
      * Set this entry's group name.
      *
      * @param groupName This entry's new group name.
      */
     public void setGroupName(String groupName) {
         this.groupName = new StringBuffer(groupName);
     }

     /**
      * Convenience method to set this entry's group and user ids.
      *
      * @param userId This entry's new user id.
      * @param groupId This entry's new group id.
      */
     public void setIds(int userId, int groupId) {
         setUserId(userId);
         setGroupId(groupId);
     }

     /**
      * Convenience method to set this entry's group and user names.
      *
      * @param userName This entry's new user name.
      * @param groupName This entry's new group name.
      */
     public void setNames(String userName, String groupName) {
         setUserName(userName);
         setGroupName(groupName);
     }

     /**
      * Set this entry's modification time. The parameter passed
      * to this method is in "Java time".
      *
      * @param time This entry's new modification time.
      */
     public void setModTime(long time) {
         modTime = time / MILLIS_PER_SECOND;
     }

     /**
      * Set this entry's modification time.
      *
      * @param time This entry's new modification time.
      */
     public void setModTime(Date time) {
         modTime = time.getTime() / MILLIS_PER_SECOND;
     }

     /**
      * Set this entry's modification time.
      *
      * @return time This entry's new modification time.
      */
     public Date getModTime() {
         return new Date(modTime * MILLIS_PER_SECOND);
     }

     /**
      * Get this entry's file.
      *
      * @return This entry's file.
      */
     public File getFile() {
         return file;
     }

     /**
      * Get this entry's mode.
      *
      * @return This entry's mode.
      */
     public int getMode() {
         return mode;
     }

     /**
      * Get this entry's file size.
      *
      * @return This entry's file size.
      */
     public long getSize() {
         return size;
     }

     /**
      * Set this entry's file size.
      *
      * @param size This entry's new file size.
      */
     public void setSize(long size) {
         this.size = size;
     }


     /**
      * Indicate if this entry is a GNU long name block
      *
      * @return true if this is a long name extension provided by GNU tar
      */
     public boolean isGNULongNameEntry() {
         return linkFlag == LF_GNUTYPE_LONGNAME
                            && name.toString().equals(GNU_LONGLINK);
     }

     /**
      * Return whether or not this entry represents a directory.
      *
      * @return True if this entry is a directory.
      */
     public boolean isDirectory() {
         if (file != null) {
             return file.isDirectory();
         }

         if (linkFlag == LF_DIR) {
             return true;
         }

         if (getName().endsWith("/")) {
             return true;
         }

         return false;
     }

     /**
      * If this entry represents a file, and the file is a directory, return
      * an array of TarEntries for this entry's children.
      *
      * @return An array of TarEntry's for this entry's children.
      */
     public TarEntry[] getDirectoryEntries() {
         if (file == null || !file.isDirectory()) {
             return new TarEntry[0];
         }

         String[]   list = file.list();
         TarEntry[] result = new TarEntry[list.length];

         for (int i = 0; i < list.length; ++i) {
             result[i] = new TarEntry(new File(file, list[i]));
         }

         return result;
     }

     /**
      * Write an entry's header information to a header buffer.
      *
      * @param outbuf The tar entry header buffer to fill in.
      */
     public void writeEntryHeader(byte[] outbuf) {
         int offset = 0;

         offset = TarUtils.getNameBytes(name, outbuf, offset, NAMELEN);
         offset = TarUtils.getOctalBytes(mode, outbuf, offset, MODELEN);
         offset = TarUtils.getOctalBytes(userId, outbuf, offset, UIDLEN);
         offset = TarUtils.getOctalBytes(groupId, outbuf, offset, GIDLEN);
         offset = TarUtils.getLongOctalBytes(size, outbuf, offset, SIZELEN);
         offset = TarUtils.getLongOctalBytes(modTime, outbuf, offset, MODTIMELEN);

         int csOffset = offset;

         for (int c = 0; c < CHKSUMLEN; ++c) {
             outbuf[offset++] = (byte) ' ';
         }

         outbuf[offset++] = linkFlag;
         offset = TarUtils.getNameBytes(linkName, outbuf, offset, NAMELEN);
         offset = TarUtils.getNameBytes(magic, outbuf, offset, MAGICLEN);
         offset = TarUtils.getNameBytes(userName, outbuf, offset, UNAMELEN);
         offset = TarUtils.getNameBytes(groupName, outbuf, offset, GNAMELEN);
         offset = TarUtils.getOctalBytes(devMajor, outbuf, offset, DEVLEN);
         offset = TarUtils.getOctalBytes(devMinor, outbuf, offset, DEVLEN);

         while (offset < outbuf.length) {
             outbuf[offset++] = 0;
         }

         long chk = TarUtils.computeCheckSum(outbuf);

         TarUtils.getCheckSumOctalBytes(chk, outbuf, csOffset, CHKSUMLEN);
     }

     /**
      * Parse an entry's header information from a header buffer.
      *
      * @param header The tar entry header buffer to get information from.
      */
     public void parseTarHeader(byte[] header) {
         int offset = 0;

         name = TarUtils.parseName(header, offset, NAMELEN);
         offset += NAMELEN;
         mode = (int) TarUtils.parseOctal(header, offset, MODELEN);
         offset += MODELEN;
         userId = (int) TarUtils.parseOctal(header, offset, UIDLEN);
         offset += UIDLEN;
         groupId = (int) TarUtils.parseOctal(header, offset, GIDLEN);
         offset += GIDLEN;
         size = TarUtils.parseOctal(header, offset, SIZELEN);
         offset += SIZELEN;
         modTime = TarUtils.parseOctal(header, offset, MODTIMELEN);
         offset += MODTIMELEN;
         offset += CHKSUMLEN;
         linkFlag = header[offset++];
         linkName = TarUtils.parseName(header, offset, NAMELEN);
         offset += NAMELEN;
         magic = TarUtils.parseName(header, offset, MAGICLEN);
         offset += MAGICLEN;
         userName = TarUtils.parseName(header, offset, UNAMELEN);
         offset += UNAMELEN;
         groupName = TarUtils.parseName(header, offset, GNAMELEN);
         offset += GNAMELEN;
         devMajor = (int) TarUtils.parseOctal(header, offset, DEVLEN);
         offset += DEVLEN;
         devMinor = (int) TarUtils.parseOctal(header, offset, DEVLEN);
     }
 }
	/*
	* Licensed to the Apache Software Foundation (ASF) under one or more
	* contributor license agreements. See the NOTICE file distributed with
	* this work for additional information regarding copyright ownership.
	* The ASF licenses this file to You under the Apache License, Version 2.0
	* (the "License"); you may not use this file except in compliance with
	* the License. You may obtain a copy of the License at
	*
	* http://www.apache.org/licenses/LICENSE-2.0
	*
	* Unless required by applicable law or agreed to in writing, software
	* distributed under the License is distributed on an "AS IS" BASIS,
	* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	* See the License for the specific language governing permissions and
	* limitations under the License.
	*
	*/

	/*
	* This package is based on the work done by Timothy Gerard Endres
	* (time@ice.com) to whom the Ant project is very grateful for his great code.
	*/

	package org.apache.tools.tar;

	import java.io.File;
	import java.util.Date;
	import java.util.Locale;

	/**
	* This class represents an entry in a Tar archive. It consists
	* of the entry's header, as well as the entry's File. Entries
	* can be instantiated in one of three ways, depending on how
	* they are to be used.
	* <p>
	* TarEntries that are created from the header bytes read from
	* an archive are instantiated with the TarEntry( byte[] )
	* constructor. These entries will be used when extracting from
	* or listing the contents of an archive. These entries have their
	* header filled in using the header bytes. They also set the File
	* to null, since they reference an archive entry not a file.
	* <p>
	* TarEntries that are created from Files that are to be written
	* into an archive are instantiated with the TarEntry( File )
	* constructor. These entries have their header filled in using
	* the File's information. They also keep a reference to the File
	* for convenience when writing entries.
	* <p>
	* Finally, TarEntries can be constructed from nothing but a name.
	* This allows the programmer to construct the entry by hand, for
	* instance when only an InputStream is available for writing to
	* the archive, and the header information is constructed from
	* other information. In this case the header fields are set to
	* defaults and the File is set to null.
	*
	* <p>
	* The C structure for a Tar Entry's header is:
	* <pre>
	* struct header {
	* char name[NAMSIZ];
	* char mode[8];
	* char uid[8];
	* char gid[8];
	* char size[12];
	* char mtime[12];
	* char chksum[8];
	* char linkflag;
	* char linkname[NAMSIZ];
	* char magic[8];
	* char uname[TUNMLEN];
	* char gname[TGNMLEN];
	* char devmajor[8];
	* char devminor[8];
	* } header;
	* </pre>
	*
	*/

	public class TarEntry implements TarConstants {
	/** The entry's name. */
	private StringBuffer name;

	/** The entry's permission mode. */
	private int mode;

	/** The entry's user id. */
	private int userId;

	/** The entry's group id. */
	private int groupId;

	/** The entry's size. */
	private long size;

	/** The entry's modification time. */
	private long modTime;

	/** The entry's link flag. */
	private byte linkFlag;

	/** The entry's link name. */
	private StringBuffer linkName;

	/** The entry's magic tag. */
	private StringBuffer magic;

	/** The entry's user name. */
	private StringBuffer userName;

	/** The entry's group name. */
	private StringBuffer groupName;

	/** The entry's major device number. */
	private int devMajor;

	/** The entry's minor device number. */
	private int devMinor;

	/** The entry's file reference */
	private File file;

	/** Maximum length of a user's name in the tar file */
	public static final int MAX_NAMELEN = 31;

	/** Default permissions bits for directories */
	public static final int DEFAULT_DIR_MODE = 040755;

	/** Default permissions bits for files */
	public static final int DEFAULT_FILE_MODE = 0100644;

	/** Convert millis to seconds */
	public static final int MILLIS_PER_SECOND = 1000;

	/**
	* Construct an empty entry and prepares the header values.
	*/
	private TarEntry () {
	this.magic = new StringBuffer(TMAGIC);
	this.name = new StringBuffer();
	this.linkName = new StringBuffer();

	String user = System.getProperty("user.name", "");

	if (user.length() > MAX_NAMELEN) {
	user = user.substring(0, MAX_NAMELEN);
	}

	this.userId = 0;
	this.groupId = 0;
	this.userName = new StringBuffer(user);
	this.groupName = new StringBuffer("");
	this.file = null;
	}

	/**
	* Construct an entry with only a name. This allows the programmer
	* to construct the entry's header "by hand". File is set to null.
	*
	* @param name the entry name
	*/
	public TarEntry(String name) {
	this();

	boolean isDir = name.endsWith("/");

	this.devMajor = 0;
	this.devMinor = 0;
	this.name = new StringBuffer(name);
	this.mode = isDir ? DEFAULT_DIR_MODE : DEFAULT_FILE_MODE;
	this.linkFlag = isDir ? LF_DIR : LF_NORMAL;
	this.userId = 0;
	this.groupId = 0;
	this.size = 0;
	this.modTime = (new Date()).getTime() / MILLIS_PER_SECOND;
	this.linkName = new StringBuffer("");
	this.userName = new StringBuffer("");
	this.groupName = new StringBuffer("");
	this.devMajor = 0;
	this.devMinor = 0;

	}

	/**
	* Construct an entry with a name and a link flag.
	*
	* @param name the entry name
	* @param linkFlag the entry link flag.
	*/
	public TarEntry(String name, byte linkFlag) {
	this(name);
	this.linkFlag = linkFlag;
	}

	/**
	* Construct an entry for a file. File is set to file, and the
	* header is constructed from information from the file.
	*
	* @param file The file that the entry represents.
	*/
	public TarEntry(File file) {
	this();

	this.file = file;

	String fileName = file.getPath();
	String osname = System.getProperty("os.name").toLowerCase(Locale.US);

	if (osname != null) {

	// Strip off drive letters!
	// REVIEW Would a better check be "(File.separator == '\')"?

	if (osname.startsWith("windows")) {
	if (fileName.length() > 2) {
	char ch1 = fileName.charAt(0);
	char ch2 = fileName.charAt(1);

	if (ch2 == ':'
	&& ((ch1 >= 'a' && ch1 <= 'z')
	\|\| (ch1 >= 'A' && ch1 <= 'Z'))) {
	fileName = fileName.substring(2);
	}
	}
	} else if (osname.indexOf("netware") > -1) {
	int colon = fileName.indexOf(':');
	if (colon != -1) {
	fileName = fileName.substring(colon + 1);
	}
	}
	}

	fileName = fileName.replace(File.separatorChar, '/');

	// No absolute pathnames
	// Windows (and Posix?) paths can start with "\\NetworkDrive\",
	// so we loop on starting /'s.
	while (fileName.startsWith("/")) {
	fileName = fileName.substring(1);
	}

	this.linkName = new StringBuffer("");
	this.name = new StringBuffer(fileName);

	if (file.isDirectory()) {
	this.mode = DEFAULT_DIR_MODE;
	this.linkFlag = LF_DIR;

	if (this.name.charAt(this.name.length() - 1) != '/') {
	this.name.append("/");
	}
	} else {
	this.mode = DEFAULT_FILE_MODE;
	this.linkFlag = LF_NORMAL;
	}

	this.size = file.length();
	this.modTime = file.lastModified() / MILLIS_PER_SECOND;
	this.devMajor = 0;
	this.devMinor = 0;
	}

	/**
	* Construct an entry from an archive's header bytes. File is set
	* to null.
	*
	* @param headerBuf The header bytes from a tar archive entry.
	*/
	public TarEntry(byte[] headerBuf) {
	this();
	parseTarHeader(headerBuf);
	}

	/**
	* Determine if the two entries are equal. Equality is determined
	* by the header names being equal.
	*
	* @param it Entry to be checked for equality.
	* @return True if the entries are equal.
	*/
	public boolean equals(TarEntry it) {
	return getName().equals(it.getName());
	}

	/**
	* Determine if the two entries are equal. Equality is determined
	* by the header names being equal.
	*
	* @param it Entry to be checked for equality.
	* @return True if the entries are equal.
	*/
	public boolean equals(Object it) {
	if (it == null \|\| getClass() != it.getClass()) {
	return false;
	}
	return equals((TarEntry) it);
	}

	/**
	* Hashcodes are based on entry names.
	*
	* @return the entry hashcode
	*/
	public int hashCode() {
	return getName().hashCode();
	}

	/**
	* Determine if the given entry is a descendant of this entry.
	* Descendancy is determined by the name of the descendant
	* starting with this entry's name.
	*
	* @param desc Entry to be checked as a descendent of this.
	* @return True if entry is a descendant of this.
	*/
	public boolean isDescendent(TarEntry desc) {
	return desc.getName().startsWith(getName());
	}

	/**
	* Get this entry's name.
	*
	* @return This entry's name.
	*/
	public String getName() {
	return name.toString();
	}

	/**
	* Set this entry's name.
	*
	* @param name This entry's new name.
	*/
	public void setName(String name) {
	this.name = new StringBuffer(name);
	}

	/**
	* Set the mode for this entry
	*
	* @param mode the mode for this entry
	*/
	public void setMode(int mode) {
	this.mode = mode;
	}

	/**
	* Get this entry's link name.
	*
	* @return This entry's link name.
	*/
	public String getLinkName() {
	return linkName.toString();
	}

	/**
	* Get this entry's user id.
	*
	* @return This entry's user id.
	*/
	public int getUserId() {
	return userId;
	}

	/**
	* Set this entry's user id.
	*
	* @param userId This entry's new user id.
	*/
	public void setUserId(int userId) {
	this.userId = userId;
	}

	/**
	* Get this entry's group id.
	*
	* @return This entry's group id.
	*/
	public int getGroupId() {
	return groupId;
	}

	/**
	* Set this entry's group id.
	*
	* @param groupId This entry's new group id.
	*/
	public void setGroupId(int groupId) {
	this.groupId = groupId;
	}

	/**
	* Get this entry's user name.
	*
	* @return This entry's user name.
	*/
	public String getUserName() {
	return userName.toString();
	}

	/**
	* Set this entry's user name.
	*
	* @param userName This entry's new user name.
	*/
	public void setUserName(String userName) {
	this.userName = new StringBuffer(userName);
	}

	/**
	* Get this entry's group name.
	*
	* @return This entry's group name.
	*/
	public String getGroupName() {
	return groupName.toString();
	}

	/**
	* Set this entry's group name.
	*
	* @param groupName This entry's new group name.
	*/
	public void setGroupName(String groupName) {
	this.groupName = new StringBuffer(groupName);
	}

	/**
	* Convenience method to set this entry's group and user ids.
	*
	* @param userId This entry's new user id.
	* @param groupId This entry's new group id.
	*/
	public void setIds(int userId, int groupId) {
	setUserId(userId);
	setGroupId(groupId);
	}

	/**
	* Convenience method to set this entry's group and user names.
	*
	* @param userName This entry's new user name.
	* @param groupName This entry's new group name.
	*/
	public void setNames(String userName, String groupName) {
	setUserName(userName);
	setGroupName(groupName);
	}

	/**
	* Set this entry's modification time. The parameter passed
	* to this method is in "Java time".
	*
	* @param time This entry's new modification time.
	*/
	public void setModTime(long time) {
	modTime = time / MILLIS_PER_SECOND;
	}

	/**
	* Set this entry's modification time.
	*
	* @param time This entry's new modification time.
	*/
	public void setModTime(Date time) {
	modTime = time.getTime() / MILLIS_PER_SECOND;
	}

	/**
	* Set this entry's modification time.
	*
	* @return time This entry's new modification time.
	*/
	public Date getModTime() {
	return new Date(modTime * MILLIS_PER_SECOND);
	}

	/**
	* Get this entry's file.
	*
	* @return This entry's file.
	*/
	public File getFile() {
	return file;
	}

	/**
	* Get this entry's mode.
	*
	* @return This entry's mode.
	*/
	public int getMode() {
	return mode;
	}

	/**
	* Get this entry's file size.
	*
	* @return This entry's file size.
	*/
	public long getSize() {
	return size;
	}

	/**
	* Set this entry's file size.
	*
	* @param size This entry's new file size.
	*/
	public void setSize(long size) {
	this.size = size;
	}


	/**
	* Indicate if this entry is a GNU long name block
	*
	* @return true if this is a long name extension provided by GNU tar
	*/
	public boolean isGNULongNameEntry() {
	return linkFlag == LF_GNUTYPE_LONGNAME
	&& name.toString().equals(GNU_LONGLINK);
	}

	/**
	* Return whether or not this entry represents a directory.
	*
	* @return True if this entry is a directory.
	*/
	public boolean isDirectory() {
	if (file != null) {
	return file.isDirectory();
	}

	if (linkFlag == LF_DIR) {
	return true;
	}

	if (getName().endsWith("/")) {
	return true;
	}

	return false;
	}

	/**
	* If this entry represents a file, and the file is a directory, return
	* an array of TarEntries for this entry's children.
	*
	* @return An array of TarEntry's for this entry's children.
	*/
	public TarEntry[] getDirectoryEntries() {
	if (file == null \|\| !file.isDirectory()) {
	return new TarEntry[0];
	}

	String[] list = file.list();
	TarEntry[] result = new TarEntry[list.length];

	for (int i = 0; i < list.length; ++i) {
	result[i] = new TarEntry(new File(file, list[i]));
	}

	return result;
	}

	/**
	* Write an entry's header information to a header buffer.
	*
	* @param outbuf The tar entry header buffer to fill in.
	*/
	public void writeEntryHeader(byte[] outbuf) {
	int offset = 0;

	offset = TarUtils.getNameBytes(name, outbuf, offset, NAMELEN);
	offset = TarUtils.getOctalBytes(mode, outbuf, offset, MODELEN);
	offset = TarUtils.getOctalBytes(userId, outbuf, offset, UIDLEN);
	offset = TarUtils.getOctalBytes(groupId, outbuf, offset, GIDLEN);
	offset = TarUtils.getLongOctalBytes(size, outbuf, offset, SIZELEN);
	offset = TarUtils.getLongOctalBytes(modTime, outbuf, offset, MODTIMELEN);

	int csOffset = offset;

	for (int c = 0; c < CHKSUMLEN; ++c) {
	outbuf[offset++] = (byte) ' ';
	}

	outbuf[offset++] = linkFlag;
	offset = TarUtils.getNameBytes(linkName, outbuf, offset, NAMELEN);
	offset = TarUtils.getNameBytes(magic, outbuf, offset, MAGICLEN);
	offset = TarUtils.getNameBytes(userName, outbuf, offset, UNAMELEN);
	offset = TarUtils.getNameBytes(groupName, outbuf, offset, GNAMELEN);
	offset = TarUtils.getOctalBytes(devMajor, outbuf, offset, DEVLEN);
	offset = TarUtils.getOctalBytes(devMinor, outbuf, offset, DEVLEN);

	while (offset < outbuf.length) {
	outbuf[offset++] = 0;
	}

	long chk = TarUtils.computeCheckSum(outbuf);

	TarUtils.getCheckSumOctalBytes(chk, outbuf, csOffset, CHKSUMLEN);
	}

	/**
	* Parse an entry's header information from a header buffer.
	*
	* @param header The tar entry header buffer to get information from.
	*/
	public void parseTarHeader(byte[] header) {
	int offset = 0;

	name = TarUtils.parseName(header, offset, NAMELEN);
	offset += NAMELEN;
	mode = (int) TarUtils.parseOctal(header, offset, MODELEN);
	offset += MODELEN;
	userId = (int) TarUtils.parseOctal(header, offset, UIDLEN);
	offset += UIDLEN;
	groupId = (int) TarUtils.parseOctal(header, offset, GIDLEN);
	offset += GIDLEN;
	size = TarUtils.parseOctal(header, offset, SIZELEN);
	offset += SIZELEN;
	modTime = TarUtils.parseOctal(header, offset, MODTIMELEN);
	offset += MODTIMELEN;
	offset += CHKSUMLEN;
	linkFlag = header[offset++];
	linkName = TarUtils.parseName(header, offset, NAMELEN);
	offset += NAMELEN;
	magic = TarUtils.parseName(header, offset, MAGICLEN);
	offset += MAGICLEN;
	userName = TarUtils.parseName(header, offset, UNAMELEN);
	offset += UNAMELEN;
	groupName = TarUtils.parseName(header, offset, GNAMELEN);
	offset += GNAMELEN;
	devMajor = (int) TarUtils.parseOctal(header, offset, DEVLEN);
	offset += DEVLEN;
	devMinor = (int) TarUtils.parseOctal(header, offset, DEVLEN);
	}
	}